chore(cmake): add CMake presets

.github/workflows/ci.yml

@@ -220,25 +220,20 @@ jobs:
         with:
           fetch-depth: 0
 
-      - name: Prepare venv
-        run: python3.13t -m venv .venv
+      - name: Prepare uv's path
+        run: echo "$HOME/.local/bin" >> $GITHUB_PATH
 
-      - name: Install Python deps
-        run: .venv/bin/pip install -r tests/requirements.txt
+      - name: Install ninja
+        run: uv tool install ninja
 
-      - name: Configure C++11
-        run: >
-          cmake -S. -Bbuild
-          -DPYBIND11_WERROR=ON
-          -DDOWNLOAD_CATCH=ON
-          -DDOWNLOAD_EIGEN=ON
-          -DPython_ROOT_DIR=.venv
+      - name: Configure via preset
+        run: cmake --preset venv -DPYBIND11_CREATE_WITH_UV=python3.13t
 
       - name: Build C++11
-        run: cmake --build build -j2
+        run: cmake --build --preset venv
 
       - name: Python tests C++11
-        run: cmake --build build --target pytest -j2
+        run: cmake --build --preset testsvenv -t pytest
 
   deadsnakes:
     strategy:
@@ -292,33 +287,27 @@ jobs:
       run: |
         sudo make install
         sudo apt-get update
-        sudo apt-get install libc6-dbg  # Needed by Valgrind
+        sudo apt-get install ninja-build libc6-dbg
 
     - name: Prepare env
       run: |
         python -m pip install -r tests/requirements.txt
 
     - name: Configure
-      run: >
-        cmake -S . -B build
-        -DCMAKE_BUILD_TYPE=Debug
-        -DPYBIND11_WERROR=ON
-        -DDOWNLOAD_CATCH=ON
-        -DDOWNLOAD_EIGEN=ON
-        -DCMAKE_CXX_STANDARD=17
+      run: cmake --preset default -DCMAKE_CXX_STANDARD=17
 
     - name: Build
-      run: cmake --build build -j 2
+      run: cmake --build --preset default
 
     - name: Python tests
-      run: cmake --build build --target pytest
+      run: cmake --build --preset default --target pytest
 
     - name: C++ tests
-      run: cmake --build build --target cpptest
+      run: cmake --build --preset default --target cpptest
 
     - name: Run Valgrind on Python tests
       if: matrix.valgrind
-      run: cmake --build build --target memcheck
+      run: cmake --build --preset default --target memcheck
 
 
   # Testing on clang using the excellent silkeh clang docker images

CMakeLists.txt

@@ -113,13 +113,60 @@ set(PYBIND11_FINDPYTHON
     ${_pybind11_findpython_default}
     CACHE STRING "Force new FindPython - NEW, OLD, COMPAT")
 
-# Allow PYTHON_EXECUTABLE if in FINDPYTHON mode and building pybind11's tests
-# (makes transition easier while we support both modes).
-if(PYBIND11_MASTER_PROJECT
-   AND PYBIND11_FINDPYTHON
-   AND DEFINED PYTHON_EXECUTABLE
-   AND NOT DEFINED Python_EXECUTABLE)
-  set(Python_EXECUTABLE "${PYTHON_EXECUTABLE}")
+if(PYBIND11_MASTER_PROJECT)
+
+  # Allow PYTHON_EXECUTABLE if in FINDPYTHON mode and building pybind11's tests
+  # (makes transition easier while we support both modes).
+  if(PYBIND11_FINDPYTHON
+     AND DEFINED PYTHON_EXECUTABLE
+     AND NOT DEFINED Python_EXECUTABLE)
+    set(Python_EXECUTABLE "${PYTHON_EXECUTABLE}")
+  endif()
+
+  if(NOT DEFINED Python3_EXECUTABLE
+     AND NOT DEFINED Python_EXECUTABLE
+     AND NOT DEFINED Python_ROOT_DIR
+     AND NOT DEFINED ENV{VIRTUALENV}
+     AND EXISTS "${CMAKE_CURRENT_SOURCE_DIR}/.venv")
+    message(STATUS "Autodetecting Python in virtual environment")
+    set(Python_ROOT_DIR "${CMAKE_CURRENT_SOURCE_DIR}/.venv")
+  endif()
+
+  # This is a shortcut that is primarily for the venv cmake preset,
+  # but can be used to quickly setup tests manually, too
+  set(PYBIND11_CREATE_WITH_UV
+      ""
+      CACHE STRING "Create a virtualenv in Python_ROOT_DIR with uv if it doesn't exist")
+
+  if(NOT PYBIND11_CREATE_WITH_UV STREQUAL "")
+    if(NOT DEFINED Python_ROOT_DIR)
+      message(FATAL_ERROR "Python_ROOT_DIR must be defined to use PYBIND11_CREATE_WITH_UV")
+    endif()
+    if(EXISTS "${Python_ROOT_DIR}")
+      message(STATUS "Using existing venv at ${Python_ROOT_DIR}, remove to recreate")
+    else()
+      find_program(UV uv REQUIRED)
+      # CMake 3.19+ would be able to use COMMAND_ERROR_IS_FATAL
+      message(
+        STATUS "Creating venv with ${UV} venv -p ${PYBIND11_CREATE_WITH_UV} '${Python_ROOT_DIR}'")
+      execute_process(COMMAND ${UV} venv -p ${PYBIND11_CREATE_WITH_UV} "${Python_ROOT_DIR}"
+                      RESULT_VARIABLE _venv_result)
+      if(_venv_result AND NOT _venv_result EQUAL 0)
+        message(FATAL_ERROR "uv venv failed with '${_venv_result}'")
+      endif()
+      message(
+        STATUS
+          "Installing deps with ${UV} pip install -p '${Python_ROOT_DIR}' -r tests/requirements.txt"
+      )
+      execute_process(
+        COMMAND ${UV} pip install -p "${Python_ROOT_DIR}" -r
+                "${CMAKE_CURRENT_SOURCE_DIR}/tests/requirements.txt" RESULT_VARIABLE _pip_result)
+      if(_pip_result AND NOT _pip_result EQUAL 0)
+        message(FATAL_ERROR "uv pip install failed with '${_pip_result}'")
+      endif()
+    endif()
+  endif()
+
 endif()
 
 # NB: when adding a header don't forget to also add it to setup.py

CMakePresets.json

@@ -0,0 +1,80 @@
+{
+  "version": 6,
+  "configurePresets": [
+    {
+      "name": "default",
+      "displayName": "Default",
+      "binaryDir": "build",
+      "generator": "Ninja",
+      "errors": {
+        "dev": true,
+        "deprecated": true
+      },
+      "cacheVariables": {
+        "CMAKE_BUILD_TYPE": "Debug",
+        "PYBIND11_FINDPYTHON": "NEW",
+        "PYBIND11_WERROR": true,
+        "DOWNLOAD_CATCH": true,
+        "DOWNLOAD_EIGEN": true
+      }
+    },
+    {
+      "name": "venv",
+      "displayName": "Venv",
+      "inherits": "default",
+      "cacheVariables": {
+        "CMAKE_BUILD_TYPE": "Debug",
+        "PYBIND11_CREATE_WITH_UV": "python3",
+        "Python_ROOT_DIR": ".venv",
+        "PYBIND11_WERROR": true,
+        "PYBIND11_FINDPYTHON": "NEW",
+        "DOWNLOAD_CATCH": true,
+        "DOWNLOAD_EIGEN": true
+      }
+    }
+  ],
+  "buildPresets": [
+    {
+      "name": "default",
+      "displayName": "Default Build",
+      "configurePreset": "default"
+    },
+    {
+      "name": "venv",
+      "displayName": "Venv Build",
+      "configurePreset": "venv"
+    },
+    {
+      "name": "tests",
+      "displayName": "Tests (for workflow)",
+      "configurePreset": "default",
+      "targets": ["pytest", "cpptest", "test_cmake_build"]
+    },
+    {
+      "name": "testsvenv",
+      "displayName": "Tests Venv (for workflow)",
+      "configurePreset": "venv",
+      "targets": ["pytest", "cpptest", "test_cmake_build"]
+    }
+  ],
+  "workflowPresets": [
+    {
+      "name": "default",
+      "displayName": "Default Workflow",
+      "steps": [
+        { "type": "configure", "name": "default" },
+        { "type": "build", "name": "default" },
+        { "type": "build", "name": "tests" }
+      ]
+    },
+    {
+      "name": "venv",
+      "displayName": "Default Workflow",
+      "steps": [
+        { "type": "configure", "name": "venv" },
+        { "type": "build", "name": "venv" },
+        { "type": "build", "name": "testsvenv" }
+      ]
+    }
+  ]
+}

pyproject.toml

@@ -13,6 +13,7 @@ ignore = [
     "pybind11/include/**",
     "pybind11/share/**",
     "CMakeLists.txt",
+    "CMakePresets.json",
     "noxfile.py",
 ]